Help! Oil pressure and VPC issues

[supra_ed]

alright, just got the supra fired up after re-re-build. first off, i shimmed the oil pump 6.25mm and i have the arizona perf. pressure line (arizona said to shim between 5-7mm.) at warm idle (havent driven it yet) oil pressure is at about 25psi, with autometer electric gauge. is that too high???? im worried wat it will do when the engine sees 7000.

secondly, i have a vpc and neo. neo is wired into vpc harness. car starts up after a few cranks and will eventually idle ok after playing with the throttle. but it will not rev over 2000rpm. a/f is around the 11 mark. vpc and neo dont seem to be having any affect when i adjust. they r not reading throttle response according to the neo. im almost positive it is wired correctly- nothing loose.

btw- 1987 7m, 40 over, forged, crower 272, a1000, 720cc
thanks in advance for any help.

 

[supra_ed]

ok, update: plugged in the afm and the neo is now reading throttle. but the vpc and the neo still dont have any effect when adjusted. car will now rev to around 3-3500 rpm but struggles to get there. it wont idle. can anyone help......im desperate lol. thanks

 

[IwantMKIII]

regaurding oil pump i don't see it as much of an issue, just monitor it as you drive later. My oil pressure hits 70-80PSI at warm up and goes to 10-15PSI idle, full throttle well, maybe 40-50 i havn't really taken notice, i always have my eyes focused elsewhere,,,,ill pay more attention next time im in the car

 

[supra_ed]

thanks man. i know on cold start it was around 75psi, havent driven it yet. please let me know what pressure ur at at high rpm and full throttle. how much did u shim it??

still need help with computer issue. this vpc is kicking my ass chuck norris style!!!

 

[spoolint78]

^^ that's about average with those shims spec's that you provided.
I wouldn't worry so much.

 

[supra_ed]

cool, cool...no worries about oil pressure.
but the vpc is pissin me off. i disconnected it, put on the lexus afm and neo and the car runs and drives ok.....i had to pull a lot of fuel considering im running greddy 720s. i would like get this damn vpc workin until i get a standalone.

 

[ATL88Supra]

rewire the VPC, there are Tons of posts regarding VPC problems

 

[supra_ed]

yeah, ive read the other posts, but i got the plug and play harness. other than the little brown wire u splice into the afm wire (which i tried both ways) there is no wiring involved. maybe i got a defective unit.....or maybe im just having a severe dumbass attack, i dont know.

 

[blackgamer16]

Double check you wired into the right wire colors. I had that problem when i got my vpc installed. Its just one of those deals where one wire is off and freaks everything out.

 

[supra_ed]

just to double-check: the brown vpc wire goes into the harness side of the afm wire, right?
im also tryin to use a afc neo, so that brown wire goes into the afc-in and the afc-out to ecu wire stays the same?
right now im just using the neo and the car runs fine (rich because of the 720s). i tried just using the vpc, without the neo, and it still wouldnt work. the car didnt even know it was there- gave check engine code for afm.

 

[quake]

just to double-check: the brown vpc wire goes into the harness side of the afm wire, right?
im also tryin to use a afc neo, so that brown wire goes into the afc-in and the afc-out to ecu wire stays the same?
right now im just using the neo and the car runs fine (rich because of the 720s). i tried just using the vpc, without the neo, and it still wouldnt work. the car didnt even know it was there- gave check engine code for afm.

first off 720cc's and a vpc is a big no no you wont be able to pull enough fuel to run properly. You need a 550cc these will do fine untill you surpass 500rwhp or so. Also the car should run with out the afc rewire the vpc then start the car if it idles ok then install the afc. Never install a bunch of new parts at once if you have a problem you wont know where to start.

 

[supra_ed]

i plan on more than 500hp. ive heard about quite a few people runnin the 720/vpc combo successfully. right now car is running on 720 and afc neo. running good, a little too rich. but im not comfortable with this- i wont run more than 12psi(on the spring) for peace of mind. i tried uninstalling neo and just hooking up vpc, still not working. any other advice anyone??? thanks for all the responses by the way!

 

[gridelock]

Whats up men ? Is it on the road yet ?

 

[bfr1992t]

Where in Ohio are you?

What brown wire are you talking about? I had the HKS harness with my VPC and there wasn't any splicing required. What I can say is the problem is in your wiring. The symptoms are what happens with the ECU does not receive an AFM signal.

Also like others have said, 720's on the stock ECU without some sort of ignition timing control is a bad idea. I ran with a similar combo (720's, VPC w/550 chip, AFC II black face) for about a year and hated it. Just make sure you keep the fuel pressure down to keep from having to tweak the afm signal down too far...33-35psi base or lower if it will start and idle, then tweak the afc using a wideband O2 sensor. Realize the 720's won't be flowing at their full rate. If I were you I'd unload the VPC/AFC combo and buy a Maft-Pro.

 

[supra_ed]

its sorta on the road....tryin to figure out this computer issue before really driving it.

im in columbus area. i have the hks harness and 550 chip in mine also. there is a brown wire coming off the vpc harness that i was told to wire into the stock afm wire. everytime i hook the vpc up, the car doesnt know its there and sends a afm code, like u said. im just tryin to get this vpc to work long enough to enjoy the car and get money together for aem. u didnt have a loose brown wire on ur vpc harness? maybe its just an 87-88 thing?? im desperate, any ideas???

 

[bfr1992t]

I've been trying to find a pic of it but cannot. I know for sure no wires had to be spliced. It was literally plug and play (I have hard wired VPC's too). There were three wires connected together with a resistor between the two large ECU connectors - this locks the factory IAT sensor to 70F. IIRC those wires were all light blue. Then there were three harness lines, one for the head unit, one for the new IAT sensor, and one for the pressure sensor. The 87/88 shouldn't be any different from what I recall.

Also you do know that when you connect the VPC you should disconnect the afm?

 

[gridelock]

hey whats is wrong with ur phone call me ?

 

[supraguy31]

On the 87-88 PNP Harness, you should have 4 wires.
Black (Ground)
Red (Power)
White (Throttle)
Grey (AFM)

The Brown wire that you are referring to that comes off the PNP harness is for the F-Con and unless you are using it, snip the wire and Tuck it down into the loom somewhere as you dont use it at all.

Its all in your wiring, Let me see if I can get my Diagram over to you as I have the VPC/SAFC installed in my car for a 87-88 with the PNP. Here is the Diagram for Wiring in the SAFC into your main harness. Disregard the 89+ ECU pinout on the side of it. you will have to find the Pinout for the 87-88 ECU which I do have, Just need to find.

 

[bfr1992t]

Ahh good call on the F-Con wire. Found some of my old VPC crap. I have a hand drawn wiring diagram somewhere too.

http://www.jobe.cc/92turbo/OLD/VPC

 

[supra_ed]

yeah i disconnected the afm.
supraguy31: if u can get me a diagram, i would really appreciate it especially with the safc wiring into the vpc.
well, ill go and triple check all the wires, thanks everyone